Body Area Networks BAN Erik Karulf eak2 cec wustl edu A survey paper written under guidance of Prof Raj Jain Download Abstract A Body Area Network is formally defined by IEEE 802 15 as a communication standard optimized for low power devices and operation on in or around the human body but not limited to humans to serve a variety of applications including medical consumer electronics personal entertainment and other IEEE 802 15 In more common terms a Body Area Network is a system of devices in close proximity to a persons body that cooperate for the benefit of the user This paper discusses several uses of the BAN technology As IEEE mentioned the most obvious application of a BAN is in the medical sector however there are also more recreational uses to BANs This paper will discuss the technologies surrounding BANs as well as several common applications for BANs At the end of the paper we will briefly discuss the challenges associated with BANs and some solutions that are on the horizon Keywords Body Area Networks Body Sensor Networks Sensor Networks Personal Area Networks Healthcare Applications IEEE 802 15 Table of Contents 1 Introduction to Body Area Network Technology 2 History and Development of BAN 3 Applications in Healthcare o 3 1 Managed Sensor Networks o 3 2 Autonomous Sensor Networks o 3 3 Case Study Cardiac Monitoring 4 Challenges associated with BAN o 4 1 Signal Path Performance o 4 2 Usability 5 Summary A References B List of Acronyms Page 1 of 10 1 Introduction The field of computer science is constantly evolving to process larger data sets and maintain higher levels of connectivity At same time advances in miniaturization allow for increased mobility and accessibility Body Area Networks represent the natural union between connectivity and miniaturization A Body Area Network BAN is defined formally as a system of devices in close proximity to a persons body that cooperate for the benefit of the user The BBC s Jo Twist gave a more informal definition of Body Area Networks in her article title When technology gets personal Inanimate objects will start to interact with us we will be surrounded on streets in homes in appliances on our bodies and possibly in our heads by things that think Forget local area networks these will be body area networks Twist04 Twist makes the possibility of BAN sound more like science fiction than a real possibility but several experts in the field expect to see BAN in production for general use by 2010 Schmidt02 While this might seem like an aggressive estimate when put into context with the history and development of BAN up to this point it becomes a much more achievable goal In the paper we will start off introducing the reader to the history and development of BAN We will cover the medical heritage of BAN and how the technology grew from a simple generalization of the concept of Body Sensor Networks BSN We will investigate current applications of BAN with an emphasis on applications in the medical sector As we cover applications of BAN we will spend a portion of the paper identifying some of technical problems facing BAN Finally we will conclude the paper with several solutions currently in development and how they hope to address and overcome the challenges inherent to BAN Back to Table of Contents 2 History and Development of BAN BAN technology is still an emerging technology and as such it has a very short history BAN technology emerges as the natural byproduct of existing sensor network technology and biomedical engineering Professor Guang Zhong Yang was the first person to formally define the phrase Body Sensor Network BSN with publication of his book Body Sensor Networks in 2006 BSN technology represents the lower bound of power and bandwidth from the BAN use case scenarios However BAN technology is quite flexible and there are many potential uses for BAN technology in addition to BSNs Some of the more common use cases for BAN technology are Page 2 of 10 Body Sensor Networks BSN Sports and Fitness Monitoring Wireless Audio Mobile Device Integration Personal Video Devices Each of these use cases have unique requirements in terms of bandwidth latency power usage and signal distance IEEE 802 15 is the working group for Wireless Personal Area Networks WPAN IEEE 802 15 The WPAN working group realized the need for a standard for use with devices inside and around close proximity to the human body IEEE 802 15 established Task Group 6 to develop the standards for BAN The BAN task group has drafted a private standard that encompasses a large range of possible devices In this way the task group has given application and device developers the decision of how to balance data rate and power Figure 1 below describes the ideal position for BAN in the power vs data rate spectrum Figure 1 Data Rate vs Power IEEE BAN SUMMARY As you can see the range of BAN devices can vary greatly in terms of bandwidth and power consumption The BAN draft requirements displayed below add a common set of requirements as to ensure that all devices conform to a similar set of behaviors yet still encompass a wide variety of devices as previously mentioned Page 3 of 10 Table 1 BAN Draft Specifications IEEE BAN SUMMARY Distance 2 m standard 5 m special use Network Density 2 4 nets m2 Network Size Max 100 devices network Power Consumption 1 mW Mbps Startup Time 100 us or 10 of Tx slot Latency end to end 10 ms Network setup time 1 sec Per device setup time excludes network initialization Effective sleep modes Operation in global license exempt band Effective sleep modes Peer to Peer and Point to Multi point communication Future proof Upgradeable scaleable backwards compatible Quality of Service Guaranteed Bandwidth Concurrent availability of asynchronous and isochronous channels Very Low Low and High duty cycle modes Allows device driven degradation of services Back to Table of Contents 3 Applications in Healthcare As previously mentioned BANs have grown as a refinement of BSN As such BSN remain the most thought out applications of BAN In his summary of the BAN task group s findings thus far Stefan Drude a researcher at Phillips outlined the possible needs the group had found for the very low BSN devices BSN devices refine the general Page 4 of 10 requirements by restricting themselves to a much smaller range 0 01 2 00 m This limited range allows developers to take advantage of several aspects of the human body First the human body itself can become a channel for short range
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